In recent years, allergic diseases caused by suspended matter, such as cedar pollen, dead mites, fungal spores, or house dust, have become a major social problem. The suspended particulate matter deposits easily on clothes or air conditioner filters. Thus, the suspended particulate matter deposited on the clothes and the filters may, in turn, detach therefrom and pollute an indoor environment. Furthermore, the suspended particulate matter decreases the sucking force or the ventilation capacity of filters in cleaners or ventilating fans.
The suspended particulate matter tends to deposit on fibrous structures having a complicated structure of rough surface and voids. Furthermore, because cedar pollen has projections, cedar pollen deposits easily on fibrous structures. Thus, cedar pollen can easily enter a house. Filters of air conditioners and their cases, ventilating fans, or cleaners composed of molded-plastic members become charged by friction. Thus, the suspended particulate matter is well known to deposit on them and become a major cause of contamination and deterioration in product functions.
Furthermore, the deposition of a liquid substance, such as soy sauce, coffee, or juice, to clothes, wallpapers, or carpets may cause stains or generate molds, which may in turn generate fungal spores. In addition, after the liquid substance dries, components contained in the liquid substance may be suspended in the air, thereby polluting an indoor environment.
As an antifouling (hereinafter also referred to as dustproof) technique for preventing the deposition of “solid dirt,” such as motes or dust, fibers on which cedar pollen hardly deposits or treatments that prevent the deposition of cedar pollen have recently been proposed. Examples of the fibers include textiles treated with a processing agent that contains a nonionic antistatic agent, silica sol containing colloidal silica modified with aluminosilicate, and an aqueous polyethylene emulsion (see, for example, Patent Document 1); cellulose-based fibers on which alumina fine particles having a size of 1.0 μm or less are deposited or cellulose-based fibers impregnated with the alumina fine particles (see, for example, Patent Document 2); and fibrous structures treated with colloidal silica and a processing liquid containing a glyoxal-based resin or a silicone resin compound (see, for example, Patent Document 3).
Treatment of clothes, wallpapers, or carpets with water-repellents is generally performed as an antifouling technique for preventing the deposition of “liquid stain” such as “soy sauce, coffee, juice, oil, dirty water, or blood” as well as “solid dirt” such as motes or dust. Examples of the water-repellents include aqueous solutions that contain an acrylate or a methacrylate each having a fluoroalkyl group and an alkoxysilane coupling agent (see, for example, Patent Document 4); processing liquids that contain an alkoxysilane and an alkyl-modified silicone oil dispersed in an organic solvent (see, for example, Patent Document 5); and compositions that include a phosphorus acid compound having a perfluoroalkyl group and a thermoplastic resin or a thermosetting resin (see, for example, Patent Document 6). These compositions are applied to the surface of fibers, such as clothing or carpets, to provide antifouling characteristics.
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2004-270039
[Patent Document 2] Japanese Unexamined Patent Application Publication No. 2005-163236
[Patent Document 3] Japanese Unexamined Patent Application Publication No. 2004-003046
[Patent Document 4] Japanese Unexamined Patent Application Publication No. 9-241622
[Patent Document 5] Japanese Unexamined Patent Application Publication No. 11-092714
[Patent Document 6] Japanese Unexamined Patent Application Publication No. 2003-096311